This invention relates to an ink-on-demand type ink jet printer and more particularly to a nozzle cover for the printer which reduces ink clogging in the print head.
Conventional ink-on-demand type ink jet printers have a print head and a pressure generating element, such as a piezo-electric or a heating element attached thereto. The head includes a nozzle for ejecting ink, an ink supply tank and a capillary tube for connecting the nozzle to the ink supply tank. In operation, ink is ejected onto a piece of paper by activating the pressure generating element by a print signal.
The print head of a conventional printer is not fully satisfactory as the air in the tip of the nozzle in the print head expands or contracts. This causes ink in the tip of the nozzle to be pushed back inward or leak from the nozzle.
Accordingly, it is desirable to provide an improved ink jet printer which has reduced clogging in the print head with limited movement of ink in the nozzle away from the tip due to an increase in air pressure.